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    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <script>
        
        function map(arr){
            for(var i=0;i<arr.length;i++){
                arr[i] = arr[i] * 1.3;
            }
            return arr;
        }
        var arr = [10,20,30,40]
        console.log(map(arr));
    </script>
</body>
</html>